首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Instrumental neutron activation analysis has been used to evaluate potentially toxic trace element concentrations in twenty-three individual food items commonly consumed in a high altitude region (Kashmir) as a continuation of our previous study. Elemental intake levels of As, Br, Hg, Sb, and Se per person per day in meat, poultry, food grains, vegetables, fruits and milk have been calculated to assess the safety of dietary intake of these items. The dietary intake values have also been compared to the RDA levels. The data will provide the base-line levels of toxic elements in food items of this region. It will also help the dieticians to formulate safe and adequate diets for the residents of this region.  相似文献   

2.
Summary Extensive use of coffee, by one-third of world's population, entails the evaluation of trace element contents in it. Instrumental neutron activation analysis (INAA) was successfully employed to determine the concentration of 20 trace elements (essential, toxic and nonessential) in four samples of coffee beans of various origins and two instant coffee brands most commonly consumed in Pakistan. This study provides the base-line values of certain toxic and essential elements in coffee. The daily intake of essential and toxic elements through coffee was estimated and compared with the recommended values. The cumulative intake of Mn is four times higher than the recommended value and that of toxic elements is well below the tolerance limits.  相似文献   

3.
Abstract

Neutron activation analysis in combination with atomic absorption spectrometry was utilized for the determination of 21 elements in integrated diet samples of the inhabitants of the Rawalpindi/Islamabad area. The study was carried out to determine prevailing concentration levels of trace elements nutrition, inadequacy, imbalances and toxicity. This data will serve as baseline values and will be helpful to monitor the degree of future contamination from foreign chemicals. The dietary intake values were also estimated and compared with the reported daily intake values. In general, the diets studied are adequate source of nutrient elements. The toxic elements intake through all the diet samples are within the safety limits.  相似文献   

4.
Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption.  相似文献   

5.
Instrumental neutron activation analysis (INAA) and electro-thermal atomic absorption spectrometry (ETAAS) were employed to determine the toxic elements in fourteen fruits harvested in Pakistan. As, Br, Hg, Sb and Se were determined using INAA. Cadmium and Pb were determined using ETAAS. The intake levels of all toxic elements have been calculated. The data show that dates supply the maximum amount of most of the toxic elements. Peels of apple and pear have also been investigated and were found to contain higher concentration of toxic elements than their edible parts. The reliability of the techniques has been established by the use of standard reference materials. This study shows that all investigated fruits cultivated and consumed in Pakistan are safe for human consumption.  相似文献   

6.
Extensive use of pan, by one-tenth of world"s population, entails the evaluation of trace element contents in its ingredients. Radiochemical neutron activation analysis (RNAA) was developed and successfully employed to determine the concentration of 36 trace elements (essential, toxic and nonessential) in its four basic ingredients, leaf of betel pepper, betel nut, catechu and lime. The radiochemical separation methodology has significantly improved the detection limits of most of these elements due to suppression of Compton background. This study provides the base-line values of certain toxic and essential elements in these ingredients. The daily intake of essential and toxic elements through pan was estimated and compared with the recommended values. The cumulative intake of Mn is four times higher than the recommended value and that of toxic elements is well below the tolerance limits.  相似文献   

7.
Instrumental neutron activation analysis (INAA) have been used to determine As, Br, Hg, Sb and Se in combination with atomic absorption spectrometry (AAS) as a complementary technique for the quantification of Cd and Pb in jaggery, brown sugar, white sugar and molasses. All sugar cane products were collected from the local sugar cane industry of Pakistan. The highest concentration of these potentially toxic elements was quantified in molasses; however, molasses together with jaggery, brown sugar and white sugar contains trace amounts of all of these elements. Due to very low concentration of Cd it could only be detected in molasses. To evaluate the percentage contribution of these elements in the sugar cane products to the weekly recommended values, intakes on weekly consumption of 100 g of each item have also been calculated which follow the pattern Br>Se>Pb>Hg>As>Sb. The elevated Br contents may be attributed to the use of Br-containing chemicals for fumigation; however, these contents are well within the tolerance levels. The estimated weekly intake of all toxic elements is very low indicating that sugar cane products can be safely ingested as part of the diets.  相似文献   

8.
Traditional medicinal seeds prescribed for specific treatment purposes, were purchased from local markets and analyzed by INAA. The samples were irradiated at Es-Salam research reactor, at a power of 5 MW for 6 h. The accuracy of the method was established by analyzing reference materials. Twenty elements were measured, with good accuracy and reproducibility. The concentration of elements determined, was found to vary depending on the seeds. The daily intake of essential and toxic elements was determined, and compared with the recommended values. The probable cumulative intake of toxic elements is well below the tolerance limits.  相似文献   

9.
10.
Toxic and essential metals content was determined by inductively coupled plasma mass spectrometry in commercial sea urchins samples from the Mediterranean Sea and Pacific Ocean. Results show that Chilean samples have the highest values of Cd, As, Ni, Cr and V; Spanish samples have the maximum Hg content while Sicilian samples have the lowest content of toxic metals. The toxic metal traces were compared with the limits of European Community (EC) No. 1881/2006 for bivalve molluscs. All samples exceed Pb and Cd limit levels; regarding Hg levels, only Sicilian and Sardinian samples have Hg content below the EC limits. The dietary intake of toxic and essential elements was evaluated for an adult. Furthermore, our study highlights a correlation between the toxic elements content and the marine environmental conditions of the places of origin even though only the generic FAO fishing area is specified.  相似文献   

11.
The elemental composition of seasoning products, like spices garlic and onion, has been reviewed paying special attention to methods proposed in the literature to determine specific elements or as much as possible components of these products which are widespread used in food preservation or food flavouring and can contribute to the intake of both, essential and toxic elements. Sample treatment and metal speciation aspects have been critically revised concerning onion, garlic and pepper (the most commonly studied products).  相似文献   

12.
A previously developed, efficient and simple on-line leaching method was used to assess the maximum bio-accessible fraction (assuming no synergistic effect from other food and beverage) of potentially toxic elements (Cr, As, Cd and Pb) in whole wheat brown and white bread samples. Artificial saliva, gastric juice and intestinal juice were successively pumped into a mini-column, packed with bread (maintained at 37 °C) connected on-line to the nebulizer of an inductively coupled plasma mass spectrometry (ICP-MS) instrument equipped with a collision-reaction interface (CRI) using hydrogen as reaction gas to minimize carbon- and chlorine-based polyatomic interferences. In contrast to the conventional batch method to which it was compared, this approach provides real-time monitoring of potentially toxic elements that are continuously released during leaching. Mass balance for both methods was verified at the 95% confidence level. Results obtained from the whole wheat brown and white bread showed that the majority of Cr, Cd and Pb was leached by gastric juice but, in contrast, the majority of As was leached by saliva. While there was higher total content for elements in whole wheat bread than in white bread, a higher percentage of elements were bio-accessible in white bread than in whole wheat bread. Both the on-line and batch methods indicate that 40–98% of toxic elements in bread samples are bio-accessible. While comparison of total analyte concentrations with provisional tolerable daily intake values may indicate some serious health concern for children, when accounting for the bio-accessibility of these elements, bread consumption is found to be safe for all ages.  相似文献   

13.
Traditional Ayurvedic remedies are easily available nowadays not only in India, their country of origin, but also in Western countries. Some of these products contain high concentrations of potentially toxic elements as main or secondary ingredients, in addition to elements essential for human health; for these reasons, it is interesting to determine their elemental composition. In this study we assessed the concentrations of fifteen elements (Al, As, Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Pb, Si and Zn) in five products of the Parpati family, a group of Ayurvedic medicines containing high concentrations of mercury, manufactured in various places in India. Concentrations were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES) or (for Pb and Cd) by graphite furnace atomic absorption spectrometry (GF-AAS) after sample mineralization. We compared the calculated daily intake of each element with reference values, considering maximum tolerable intake levels or recommended nutrient amounts. The experimental results were treated with chemometric pattern recognition techniques. We found differences in the composition of products of the same denomination manufactured by different companies and strong correlations among groups of variables. As expected, the daily intake of mercury upon consumption of Parpati medicines largely exceeded the tolerable intake level of this element.  相似文献   

14.
The intake of leafy vegetables in daily diet is very important to meet our nutritional needs. Vegetables provide the essential elements which are necessary and recommended for human growth. However, due to rapid industrialization and urbanization our environment becomes polluted and this affects the normal growth of agricultural products and composition of environmental species. The elemental concentrations present in the environmental samples are good indicators to assess the toxicological levels due to pollution affects. In the present work we have analysed several vegetable plant samples by instrumental neutron activation analysis to determine the elemental concentrations at major, minor and trace levels. The leafy vegetables like spinach, red leafy veagetable, pui, gourd leaf, lettuce and katoua were chosen as these are extensively consumed by local peple in eastern part of India. We have determined 15 elements in the above mentioned vegetable samples and some of these are essential elements and some are toxic elements. It was found that Na and K were present as major elements, Fe and Zn as minor elements and As, Ce, Cr, Co, La, Mo, Rb, Sc, Sm, Sr as trace elements. The concentration level of Cr was found to be higher than that of recommended value certified by WHO and National environment quality control for human consumption. The validation of our analytical results have been performed by the Z-score tests through the determination of concentrations of the elements of interest in certified reference materials.  相似文献   

15.
The concentration of lead and cadmium in different kinds of milk samples (powdered, infant formula, market, buffalo, condensed and human) were determined using electrothermal atomic absorption spectrophotometric technique. Among all the varieties of milk analysed, condensed milk was found to contain much higher amount of lead. Human milk as expected was found to have lowest concentration of these elements. The results were compared with the reported values of other countries. Daily intake of these toxic elements by adults and babies up to the age of six months through the consumption of various types of milk was estimated and compared with the tolerance levels.  相似文献   

16.
This study reports the determination of trace essential (Co, Cr, Cu, Se, and Zn) and toxic (Al, As, Cd, Hg, and Pb) elements in greenhouse tomatoes, peppers, and cucumbers from supermarkets of Seoul, Busan, Gangneung, Daegu, Daejeon, and Gwangju, South Korea using inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectroscopy, and direct mercury analysis. The methods were validated by linearity, limits of detection and quantification, precision, accuracy, and recovery measurements that provided satisfactory results in all cases. Among the essential trace elements, Zn was found to have the highest concentrations (0.84–2.5?mg/kg) followed by Cu (0.21–0.62?mg/kg) and Cr (0.01–0.06?mg/kg). The mean concentrations (mg/kg) of the toxic elements were in the order Al?>?Pb?>?As?>?Cd?>?Hg for tomatoes and cucumbers and Al?>?Pb?>?Cd?>?As?>?Hg for peppers; all were below the permissible limits set by World Health Organization for human consumption. The estimated dietary intake, target hazard quotients (THQs), and hazard indices of the samples were within safe levels. The combined THQ values for the toxic elements in the vegetables were from 0.002 to 0.012 with significant contribution from arsenic, aluminum, cadmium, and mercury. The results of this study show that trace and toxic elements in the analyzed vegetables do not impose any serious health harmful effects for the population upon consumption.  相似文献   

17.
Extensive use of chewing gums, by children in particular, entails the evaluation of trace element contents in them. Radiochemical neutron activation analysis (RNAA) was successfully employed to determine the concentration of 35 trace elements (essential, toxic and nonessential) in eight different brands of chewing gum generally consumed in Rawalpindi/Islamabad area. Comparison of trace element data of our work with literature has been presented. None of the elements detected in the brands of chewing gum examined was found to be present at a level representing a substantial contribution to the total dietary intake of the element.  相似文献   

18.
Abstract

The concentrations of lead and cadmium in different kinds of milk samples (powdered, infant formula, market, buffalo, condensed and human) were determined using electrothermal atomic absorption spectrophotometric technique. Among all the varieties of milk analysed, condensed milk was found to contain much higher amount of lead. Human milk as expected was found to have lowest concentration of these elements. The results were compared with the reported values of other countries. Daily intake of these toxic elements by adults and babies up to the age of six months through the consumption of various types of milk was estimated and compared with the tolerance levels.  相似文献   

19.

The occurrence of 210Pb, 210Po, trace elements was assessed in a selection of berries on commercial sale in Italy. Data confirmed that berries might serve as an important source of essential elements. The 210Pb, 210Po concentrations found were higher than the reference values reported by UNSCEAR for roots and fruits in the world. There is no risk whatsoever from the intake of toxic elements as Al, As, Cd, Pb, Ni, Hg in berriberries analyzed; it is necessary, however, continuously monitored the levels of these elements to protect consumers against potential adverse health effects especially when consumed in large quantities.

  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号